Examples of uses of artificial intelligence at work
This is an interesting question in that it addresses how AI becomes a part of our mundane existence.  

@JadenTravnik's pithy comment is quite correct--spam filtering is a form of AI that that it so fundamental to the information eco system that it has become nearly invisible. 

It's useful to be able to define what we mean by Artificial (or Algorithmic) Intelligence, and to distinguish it from computation in general.  A fundamental distinction is that AI makes decisions as opposed to merely crunching numbers.

My feeling is that applied AI is still a very specialized field, so that people using it dynamically to solve problems at work today are those who work in the field of AI, as opposed to workers in general.  

You may find this related question useful: Is AI programming useful in everyday programs?

This may change in the future, where a type of expert system, for instance, could assist a worker by presenting it's own analysis and conclusions on a decision problem. But in most office settings, that type of reasoning is still the domain of humans.

My advice would be to continue on Jaden's track, looking for examples of where AI underlies everyday functions.